Re: tuning concurrent_reads param

2014-11-06 Thread Bryan Talbot
On Wed, Nov 5, 2014 at 11:00 PM, Jimmy Lin y2klyf+w...@gmail.com wrote: Sorry I have late follow up question In the Cassandra.yaml file the concurrent_read section has the following comment: What does it mean by the operations to enqueue low enough in the stack that the OS and drives

Re: new data not flushed to sstables

2014-11-03 Thread Bryan Talbot
On Mon, Nov 3, 2014 at 7:44 AM, Sebastian Martinka sebastian.marti...@mercateo.com wrote: System and Keyspace Information: 4 Nodes CREATE KEYSPACE restore_test WITH replication = { 'class': 'SimpleStrategy', 'replication_factor': '3'}; I assumed, that a flush write all data

Re: OldGen saturation

2014-10-28 Thread Bryan Talbot
On Tue, Oct 28, 2014 at 9:02 AM, Adria Arcarons adria.arcar...@greenpowermonitor.com wrote: Hi, Hi We have about 50.000 CFs of varying size The writing test consists of a continuous flow of inserts. The inserts are done inside BATCH statements in groups of 1.000 to a single CF

Re: Repair taking long time

2014-09-26 Thread Bryan Talbot
With a 4.5 TB table and just 4 nodes, repair will likely take forever for any version. -Bryan On Fri, Sep 26, 2014 at 10:40 AM, Jonathan Haddad j...@jonhaddad.com wrote: Are you using Cassandra 2.0 vnodes? If so, repair takes forever. This problem is addressed in 2.1. On Fri, Sep 26,

Re: Query first 1 columns for each partitioning keys in CQL?

2014-05-19 Thread Bryan Talbot
I think there are several issues in your schema and queries. First, the schema can't efficiently return the single newest post for every author. It can efficiently return the newest N posts for a particular author. On Fri, May 16, 2014 at 11:53 PM, 後藤 泰陽 matope@gmail.com wrote: But I

Re: Best partition type for Cassandra with JBOD

2014-05-19 Thread Bryan Talbot
Google+ profilehttps://plus.google.com/102718274791889610666/posts http://spinn3r.com War is peace. Freedom is slavery. Ignorance is strength. Corporations are people. -- Bryan Talbot Architect / Platform team lead, Aeria Games and Entertainment Silicon Valley | Berlin | Tokyo | Sao

Re: Index with same Name but different keyspace

2014-05-19 Thread Bryan Talbot
On Mon, May 19, 2014 at 6:39 AM, mahesh rajamani rajamani.mah...@gmail.comwrote: Sorry I just realized the table name in 2 schema are slightly different, but still i am not sure why i should not use same index name across different schema. Below is the instruction to reproduce. Created 2

Failed to mkdirs $HOME/.cassandra

2014-05-15 Thread Bryan Talbot
How should nodetool command be run as the user nobody? The nodetool command fails with an exception if it cannot create a .cassandra directory in the current user's home directory. I'd like to schedule some nodetool commands to run with least privilege as cron jobs. I'd like to run them as the

Re: Cassandra 2.0.7 always failes due to 'too may open files' error

2014-05-05 Thread Bryan Talbot
Running # cat /proc/$(cat /var/run/cassandra.pid)/limits as root or your cassandra user will tell you what limits it's actually running with. On Sun, May 4, 2014 at 10:12 PM, Yatong Zhang bluefl...@gmail.com wrote: I am running 'repair' when the error occurred. And just a few days before

Re: using cssandra cql with php

2014-03-04 Thread Bryan Talbot
I think the options for using CQL from PHP pretty much don't exist. Those that do are very old, haven't been updated in months, and don't support newer CQL features. Also I don't think any of them use the binary protocol but use thrift instead. From what I can tell, you'll be stuck using old CQL

Re: Heap is not released and streaming hangs at 0%

2013-06-21 Thread Bryan Talbot
bloom_filter_fp_chance = 0.7 is probably way too large to be effective and you'll probably have issues compacting deleted rows and get poor read performance with a value that high. I'd guess that anything larger than 0.1 might as well be 1.0. -Bryan On Fri, Jun 21, 2013 at 5:58 AM, srmore

Re: Compaction not running

2013-06-18 Thread Bryan Talbot
Manual compaction for LCS doesn't really do much. It certainly doesn't compact all those little files into bigger files. What makes you think that compactions are not occurring? -Bryan On Tue, Jun 18, 2013 at 3:59 PM, Franc Carter franc.car...@sirca.org.auwrote: On Sat, Jun 15, 2013 at

Re: [Cassandra] Conflict resolution in Cassandra

2013-06-06 Thread Bryan Talbot
For generic questions like this, google is your friend: http://lmgtfy.com/?q=cassandra+conflict+resolution -Bryan On Thu, Jun 6, 2013 at 11:23 AM, Emalayan Vairavanathan svemala...@yahoo.com wrote: Hi All, Can someone tell me about the conflict resolution mechanisms provided by Cassandra?

Re: Multiple JBOD data directory

2013-06-05 Thread Bryan Talbot
If you're using cassandra 1.2 then you have a choice specified in the yaml # policy for data disk failures: # stop: shut down gossip and Thrift, leaving the node effectively dead, but # can still be inspected via JMX. # best_effort: stop using the failed disk and respond to requests based

Re: Multiple JBOD data directory

2013-06-05 Thread Bryan Talbot
sstables. This means you WILL see obsolete # data at CL.ONE! # ignore: ignore fatal errors and let requests fail, as in pre-1.2 Cassandra disk_failure_policy: stop On Wed, Jun 5, 2013 at 2:59 PM, Bryan Talbot btal...@aeriagames.com wrote: If you're using cassandra 1.2 then you have

Re: Cassandra performance decreases drastically with increase in data size.

2013-05-30 Thread Bryan Talbot
One or more of these might be effective depending on your particular usage - remove data (rows especially) - add nodes - add ram (has limitations) - reduce bloom filter space used by increasing fp chance - reduce row and key cache sizes - increase index sample ratio - reduce compaction

Re: data clean up problem

2013-05-28 Thread Bryan Talbot
I think what you're asking for (efficient removal of TTL'd write-once data) is already in the works but not until 2.0 it seems. https://issues.apache.org/jira/browse/CASSANDRA-5228 -Bryan On Tue, May 28, 2013 at 1:26 PM, Hiller, Dean dean.hil...@nrel.gov wrote: Oh and yes, astyanax uses

Re: In a multiple data center setup, do all the data centers have complete data irrespective of RF?

2013-05-20 Thread Bryan Talbot
Option #3 since it depends on the placement strategy and not the partitioner. -Bryan On Mon, May 20, 2013 at 6:24 AM, Pinak Pani nishant.has.a.quest...@gmail.com wrote: I just wanted to verify the fact that if I happen to setup a multi data-center Cassandra setup, will each data center

Re: In a multiple data center setup, do all the data centers have complete data irrespective of RF?

2013-05-20 Thread Bryan Talbot
On Mon, May 20, 2013 at 10:01 AM, Pinak Pani nishant.has.a.quest...@gmail.com wrote: Assume NetworkTopologyStrategy. So, I wanted to know whether a data-center will contain all the keys? This is the case: CREATE KEYSPACE appKS WITH placement_strategy = 'NetworkTopologyStrategy' AND

Re: update does not apply to any replica if consistency = ALL and one replica is down

2013-05-17 Thread Bryan Talbot
I think you're conflating may with must. That article says that updates may still be applied to some replicas when there is a failure and I believe that still is the case. However, if the coordinator knows that the CL can't be met before even attempting the write, I don't think it will attempt

Re: SSTable size versus read performance

2013-05-16 Thread Bryan Talbot
512 sectors for read-ahead. Are your new fancy SSD drives using large sectors? If your read-ahead is really reading 512 x 4KB per random IO, then that 2 MB per read seems like a lot of extra overhead. -Bryan On Thu, May 16, 2013 at 12:35 PM, Keith Wright kwri...@nanigans.com wrote: We

Re: index_interval

2013-05-13 Thread Bryan Talbot
. -Bryan On Fri, May 10, 2013 at 7:44 PM, Edward Capriolo edlinuxg...@gmail.comwrote: If you use your off heap memory linux has an OOM killer, that will kill a random tasks. On Fri, May 10, 2013 at 11:34 AM, Bryan Talbot btal...@aeriagames.comwrote: If off-heap memory (for indes samples, bloom

Re: index_interval

2013-05-10 Thread Bryan Talbot
If off-heap memory (for indes samples, bloom filters, row caches, key caches, etc) is exhausted, will cassandra experience a memory allocation error and quit? If so, are there plans to make the off-heap usage more dynamic to allow less used pages to be replaced with hot data and the paged-out /

Re: Cassandra running High Load with no one using the cluster

2013-05-06 Thread Bryan Talbot
On Sat, May 4, 2013 at 9:22 PM, Aiman Parvaiz ai...@grapheffect.com wrote: When starting this cluster we set JVM_OPTS=$JVM_OPTS -Xss1000k Why did you increase the stack-size to 5.5 times greater than recommended? Since each threads now uses 1000KB minimum just for the stack, a large

Re: Adding nodes in 1.2 with vnodes requires huge disks

2013-04-26 Thread Bryan Talbot
I believe that nodetool rebuild is used to add a new datacenter, not just a new host to an existing cluster. Is that what you ran to add the node? -Bryan On Fri, Apr 26, 2013 at 1:27 PM, John Watson j...@disqus.com wrote: Small relief we're not the only ones that had this issue. We're

Re: Cassandra services down frequently [Version 1.1.4]

2013-04-04 Thread Bryan Talbot
On Thu, Apr 4, 2013 at 1:27 AM, adeel.ak...@panasiangroup.com wrote: After some time (1 hour / 2 hour) cassandra shut services on one or two nodes with follwoing errors; Wonder what the workload and schema is like ... We can see from below that you've tweaked and disabled many of the

Re: Timeseries data

2013-03-27 Thread Bryan Talbot
In the worst case, that is possible, but compaction strategies try to minimize the number of SSTables that a row appears in so a row being in ALL SStables is not likely for most cases. -Bryan On Wed, Mar 27, 2013 at 12:17 PM, Kanwar Sangha kan...@mavenir.com wrote: Hi – I have a query on

Re: old data / tombstones are not deleted after ttl

2013-03-04 Thread Bryan Talbot
Those older files won't be included in a compaction until there are min_compaction_threshold (4) files of that size. When you get another SS table -Data.db file that is about 12-18GB then you'll have 4 and they will be compacted together into one new file. At that time, if there are any rows

Re: Reading old data problem

2013-02-28 Thread Bryan Talbot
On Thu, Feb 28, 2013 at 5:08 PM, Víctor Hugo Oliveira Molinar vhmoli...@gmail.com wrote: Ok guys let me try to ask it in a different way: Will repair totally ensure a data synchronism among nodes? If there are no writes happening on the cluster then yes. Otherwise, the answer is it depends

Re: heap usage

2013-02-15 Thread Bryan Talbot
Aren't bloom filters kept off heap in 1.2? https://issues.apache.org/jira/browse/CASSANDRA-4865 Disabling bloom filters also disables tombstone removal as well, so don't disable them if you delete anything. https://issues.apache.org/jira/browse/CASSANDRA-5182 I believe that the index samples

Re: Deletion consistency

2013-02-15 Thread Bryan Talbot
With a RF and CL of one, there is no replication so there can be no issue with distributed deletes. Writes (and reads) can only go to the one host that has the data and will be refused if that node is down. I'd guess that your app isn't deleting records when you think that it is, or that the

Re: Cluster not accepting insert while one node is down

2013-02-14 Thread Bryan Talbot
Generally data isn't written to whatever node the client connects to. In your case, a row is written to one of the nodes based on the hash of the row key. If that one replica node is down, it won't matter which coordinator node you attempt a write with CL.ONE: the write will fail. If you want

Re: Upgrade from 0.6.x to 1.2.x

2013-02-07 Thread Bryan Talbot
Wow, that's pretty ambitions expecting an upgrade which skips 4 major versions (0.7, 0.8, 1.0, 1.1) to work. I think you're going to have to follow the upgrade path for each of those intermediate steps and not upgrade in one big jump. -Bryan On Thu, Feb 7, 2013 at 3:41 AM, Sergey Leschenko

Re: too many warnings of Heap is full

2013-01-30 Thread Bryan Talbot
My guess is that those one or two nodes with the gc pressure also have more rows in your big CF. More rows could be due to imbalanced distribution if your'e not using a random partitioner or from those nodes not yet removing deleted rows which other nodes may have done. JVM heap space is used

Re: LCS not removing rows with all TTL expired columns

2013-01-22 Thread Bryan Talbot
the load as desired at the expense of additional jvm memory. -Bryan On Thu, Jan 17, 2013 at 6:50 PM, Bryan Talbot btal...@aeriagames.comwrote: Bleh, I rushed out the email before some meetings and I messed something up. Working on reproducing now with better notes this time. -Bryan

Re: LCS not removing rows with all TTL expired columns

2013-01-17 Thread Bryan Talbot
. ** ** Cheers ** ** - Aaron Morton Freelance Cassandra Developer New Zealand ** ** @aaronmorton http://www.thelastpickle.com ** ** On 17/01/2013, at 2:55 PM, Bryan Talbot btal...@aeriagames.com wrote

Re: LCS not removing rows with all TTL expired columns

2013-01-17 Thread Bryan Talbot
, 'test'); // Insert records while( 1 ) { $testCf-insert(UUID::uuid1(), array(a = 1), null, 120); } // Close our connections $pool-close(); $sys-close(); ? -Bryan On Thu, Jan 17, 2013 at 10:11 AM, Bryan Talbot btal...@aeriagames.comwrote: We are using LCS and the particular row I've

Re: LCS not removing rows with all TTL expired columns

2013-01-17 Thread Bryan Talbot
you are setting gc_grace to 0 (although I could just be blind, it happens). On Thu, Jan 17, 2013 at 5:01 PM, Bryan Talbot btal...@aeriagames.comwrote: I'm able to reproduce this behavior on my laptop using 1.1.5, 1.1.7, 1.1.8, a trivial schema, and a simple script that just inserts rows

LCS not removing rows with all TTL expired columns

2013-01-16 Thread Bryan Talbot
On cassandra 1.1.5 with a write heavy workload, we're having problems getting rows to be compacted away (removed) even though all columns have expired TTL. We've tried size tiered and now leveled and are seeing the same symptom: the data stays around essentially forever. Currently we write all

Re: LCS not removing rows with all TTL expired columns

2013-01-16 Thread Bryan Talbot
that CF gets compacted I guess your expired columns are propagated to high tier CF, which gets compacted rarely. So, you have to wait when high tier CF gets compacted. Andrey On Wed, Jan 16, 2013 at 11:39 AM, Bryan Talbot btal...@aeriagames.comwrote: On cassandra 1.1.5 with a write heavy

Re: State of Cassandra and Java 7

2012-12-21 Thread Bryan Talbot
Brian, did any of your issues with java 7 result in corrupting data in cassandra? We just ran into an issue after upgrading a test cluster from Cassandra 1.1.5 and Oracle JDK 1.6.0_29-b11 to Cassandra 1.1.7 and 7u10. What we saw is values in columns with validation

Re: CQL timestamps and timezones

2012-12-07 Thread Bryan Talbot
With 1.1.5, the TS is displayed with the local timezone and seems correct. cqlsh:bat create table test (id uuid primary key, ts timestamp ); cqlsh:bat insert into test (id,ts) values ( '89d09c88-40ac-11e2-a1e2-6067201fae78', '2012-12-07T10:00:00-'); cqlsh:bat select * from test; id

Re: need some help with row cache

2012-11-28 Thread Bryan Talbot
alone are not enough, and I must also specify the caching attribute on a per column family basis? -- Y. On Tue, Nov 27, 2012 at 11:57 PM, Bryan Talbot btal...@aeriagames.com wrote: On Tue, Nov 27, 2012 at 8:16 PM, Yiming Sun yiming@gmail.com wrote: Hello, but it is not clear to me

Re: outOfMemory error

2012-11-28 Thread Bryan Talbot
Well, asking for 500MB of data at once for a server with such modest specs is asking for troubles. Here are my suggestions. Disable the 1 GB row cache Consider allocating that memory for the java heap Xms2500m Xmx2500m Don't fetch all the columns at once -- page through them a slice at a time

Re: need some help with row cache

2012-11-27 Thread Bryan Talbot
On Tue, Nov 27, 2012 at 8:16 PM, Yiming Sun yiming@gmail.com wrote: Hello, but it is not clear to me where this setting belongs to, because even in the v1.1.6 conf/cassandra.yaml, there is no such property, and apparently adding this property to the yaml causes a fatal configuration

Re: Admin for cassandra?

2012-11-16 Thread Bryan Talbot
The https://github.com/sebgiroux/Cassandra-Cluster-Admin app does some of what you're asking. It allows basic browsing and some admin functionality. If you want to run actual CQL queries though, you currently need to use another app for that (like cqlsh). -Bryan On Thu, Nov 15, 2012 at 11:30

Re: How to upgrade a ring (0.8.9 nodes) to 1.1.5 with the minimal downtime?

2012-11-05 Thread Bryan Talbot
Do a rolling upgrade of the ring to 1.0.12 first and then upgrade to 1.1.x. After each rolling upgrade, you should probably do the recommend nodetool upgradesstables, etc. The datastax documentation about upgrading might be helpful for you: http://www.datastax.com/docs/1.1/install/upgrading

Re: repair, compaction, and tombstone rows

2012-11-05 Thread Bryan Talbot
As the OP of this thread, it is a big itch for my use case. Repair ends up streaming tens of gigabytes of data which has expired TTL and has been compacted away on some nodes but not yet on others. The wasted work is not nice plus it drives up the memory usage (for bloom filters, indexes, etc)

Re: repair, compaction, and tombstone rows

2012-11-01 Thread Bryan Talbot
It seems like CASSANDRA-3442 might be an effective fix for this issue assuming that I'm reading it correctly. It sounds like the intent is to automatically compact SSTables when a certain percent of the columns are gcable by being deleted or with expired tombstones. Is my understanding correct?

Re: Cassandra upgrade issues...

2012-11-01 Thread Bryan Talbot
Note that 1.0.7 came out before 1.1 and I know there were some compatibility issues that were fixed in later 1.0.x releases which could affect your upgrade. I think it would be best to first upgrade to the latest 1.0.x release, and then upgrade to 1.1.x from there. -Bryan On Thu, Nov 1, 2012

repair, compaction, and tombstone rows

2012-10-31 Thread Bryan Talbot
I've been experiencing a behavior that is undesirable and it seems like a bug that causes a high amount of wasted work. I have a CF where all columns have a TTL, are generally all inserted in a very short period of time (less than a second) and are never over-written or explicitly deleted.

Re: constant CMS GC using CPU time

2012-10-25 Thread Bryan Talbot
On Thu, Oct 25, 2012 at 4:15 AM, aaron morton aa...@thelastpickle.comwrote: This sounds very much like my heap is so consumed by (mostly) bloom filters that I am in steady state GC thrash. Yes, I think that was at least part of the issue. The rough numbers I've used to estimate working

Re: constant CMS GC using CPU time

2012-10-24 Thread Bryan Talbot
On Wed, Oct 24, 2012 at 2:38 PM, Rob Coli rc...@palominodb.com wrote: On Mon, Oct 22, 2012 at 8:38 AM, Bryan Talbot btal...@aeriagames.com wrote: The nodes with the most data used the most memory. All nodes are affected eventually not just one. The GC was on-going even when the nodes

Re: constant CMS GC using CPU time

2012-10-23 Thread Bryan Talbot
JVM_OPTS=$JVM_OPTS -XX:+UseCompressedOops You are too far behind the reference JVM's. Parallel GC is the preferred and highest performing form in the current Security Baseline version of the JVM's. -- Bryan Talbot Architect / Platform team lead, Aeria Games and Entertainment Silicon Valley

Re: constant CMS GC using CPU time

2012-10-23 Thread Bryan Talbot
On Mon, Oct 22, 2012 at 6:05 PM, aaron morton aa...@thelastpickle.comwrote: The GC was on-going even when the nodes were not compacting or running a heavy application load -- even when the main app was paused constant the GC continued. If you restart a node is the onset of GC activity

Re: constant CMS GC using CPU time

2012-10-22 Thread Bryan Talbot
compaction, repair and throughput. Hope that helps. - Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 20/10/2012, at 6:59 AM, Bryan Talbot btal...@aeriagames.com wrote: ok, let me try asking the question a different way ... How does

Re: constant CMS GC using CPU time

2012-10-19 Thread Bryan Talbot
actually is. That's not such a good thing. -Bryan On Thu, Oct 18, 2012 at 11:06 AM, Bryan Talbot btal...@aeriagames.comwrote: In a 4 node cluster running Cassandra 1.1.5 with sun jvm 1.6.0_29-b11 (64-bit), the nodes are often getting stuck in state where CMS collections of the old space

constant CMS GC using CPU time

2012-10-18 Thread Bryan Talbot
In a 4 node cluster running Cassandra 1.1.5 with sun jvm 1.6.0_29-b11 (64-bit), the nodes are often getting stuck in state where CMS collections of the old space are constantly running. The JVM configuration is using the standard settings in cassandra-env -- relevant settings are included below.

Re: hadoop consistency level

2012-10-18 Thread Bryan Talbot
I believe that reading with CL.ONE will still cause read repair to be run (in the background) 'read_repair_chance' of the time. -Bryan On Thu, Oct 18, 2012 at 1:52 PM, Andrey Ilinykh ailin...@gmail.com wrote: On Thu, Oct 18, 2012 at 1:34 PM, Michael Kjellman mkjell...@barracuda.com wrote:

Re: MBean cassandra.db.CompactionManager TotalBytesCompacted counts backwards

2012-10-08 Thread Bryan Talbot
, 2012 at 7:27 PM, Bryan Talbot btal...@aeriagames.com wrote: I've recently added compaction rate (in bytes / second) to my monitors for cassandra and am seeing some odd values. I wasn't expecting the values for TotalBytesCompacted to sometimes decrease from one reading to the next

Re: what's the most 1.1 stable version?

2012-10-05 Thread Bryan Talbot
? Cheers, Alex -- Bryan Talbot Architect / Platform team lead, Aeria Games and Entertainment Silicon Valley | Berlin | Tokyo | Sao Paulo

MBean cassandra.db.CompactionManager TotalBytesCompacted counts backwards

2012-10-05 Thread Bryan Talbot
I've recently added compaction rate (in bytes / second) to my monitors for cassandra and am seeing some odd values. I wasn't expecting the values for TotalBytesCompacted to sometimes decrease from one reading to the next. It seems that the value should be monotonically increasing while a server

is Not a time-based UUID serious?

2012-09-12 Thread Bryan Talbot
I'm testing upgrading a multi-node cluster from 1.0.9 to 1.1.5 and ran into the error message described here: https://issues.apache.org/jira/browse/CASSANDRA-4195 What I can't tell is if this is a serious issue or if it can be safely ignored. If it is a serious issue, shouldn't the migration

Re: is Not a time-based UUID serious?

2012-09-12 Thread Bryan Talbot
. -Bryan On Wed, Sep 12, 2012 at 2:42 PM, Bryan Talbot btal...@aeriagames.comwrote: I'm testing upgrading a multi-node cluster from 1.0.9 to 1.1.5 and ran into the error message described here: https://issues.apache.org/jira/browse/CASSANDRA-4195 What I can't tell is if this is a serious issue